Image printing apparatus

ABSTRACT

Image printing apparatus including an exposure head for making a line-by-line exposure of a light-sensitive material, a positioning member facing the exposure head and having a projecting part situated on an optical axis of the exposure head on a side facing the exposure head, a first transfer path on an upstream side of the positioning member to transfer the material toward the positioning member, and a second transfer path on a downstream side of the positioning member to transfer the material downstream. The projecting part is located on a side closer to the exposure head than the intersection between an extension of the first transfer path and the optical axis and the intersection of an extension of the second transfer path and the optical axis. The positioning member has on its upstream side an inclined portion for guiding a forward end of the material transferred from the first transfer path onto the projecting part.

TECHNICAL FIELD

This invention relates to an image exposure apparatus having an exposureunit for exposing a light-sensitive material, such as photographicprinting paper, line by line as the material is transferred in aspecified direction.

BACKGROUND ART

Conventionally, an image exposure apparatus of this kind comprises anexposure unit 101 including a lead lanthanum zirconate titanate (PLZT)device, for instance, a positioning member 102 disposed face to facewith the exposure unit 101, a first pair of transfer rollers 103 locatedupstream of the exposure unit 101 and a second pair of transfer rollers104 located downstream of the exposure unit 101 as shown in FIG. 11, forexample, wherein image exposure operation is performed by exposing alight-sensitive material P like photographic printing paper which isgripped between the first transfer rollers 103 and between the secondtransfer rollers 104 and transferred over the top surface of thepositioning member 102 with a digital image projected line by line bythe exposure unit 101. The PLZT device is a shutter array formed of atransparent ferroelectric ceramic material, which is obtained by addinglanthanum to lead zirconate titanate, and utilizes an electro-opticaleffect of the material.

In the image exposure apparatus thus constructed, the light-sensitivematerial P would scarcely lift upward apart from the positioning member102 by between the first transfer rollers 103 on the upstream side andthe second transfer rollers 104 on the downstream side, where thelight-sensitive material P is gripped, even when the light-sensitivematerial is somewhat curled, because it is pulled by the transfer rollerpairs 103, 104 on both sides. It is therefore possible to properlyexpose the light-sensitive material P.

If, however, the light-sensitive material P is curled even slightly, itsforward portion would lift apart from the positioning member 102,creating an out-of-focus condition and making it impossible to properlyexpose this portion, because the forward portion of the light-sensitivematerial P is not gripped by the second transfer roller pair 104 on thedownstream side. Similarly, if the light-sensitive material P is curledeven slightly, its rear portion would lift apart from the positioningmember 102, creating an out-of-focus condition and making it impossibleto properly expose this portion, because the rear portion of thelight-sensitive material P is not gripped by the first transfer rollerpair 103 on the upstream side. In particular, the exposure unit whichexposes line by line generally has a large depth of focus and, in mostcases, maximum permissible displacement of the light-sensitive materialalong the optical axis of the exposure unit is only about ±0.1 mm sothat the exposure operation is likely to be affected by the curl.

Thus, it has often been necessary in the image exposure apparatus of theprior art to cut and discard the forward and rear portions of thelight-sensitive material P, developing a problem that losses of thelight-sensitive material are caused. A further problem has been that ifthe forward and rear portions were to be cut, processing capabilitywould be decreased by as much as the time required for cuttingoperation.

This invention has been made in consideration of the aforementionedsituations. It is therefore an object of the invention to provide imageexposure apparatus which can properly expose forward and rear portionsof a light-sensitive material even when it is curled.

SUMMARY OF THE INVENTION

To achieve the aforementioned object, an image exposure apparatusaccording to the invention comprises an exposure device for makingline-by-line exposures of a light-sensitive material on an optical axis,a positioning member provided at a position facing said exposure deviceand having a projecting part situated on said optical axis on a sidefacing said exposure device, a first transfer path provided on anupstream side of said positioning member to transfer saidlight-sensitive material toward said positioning member, and a secondtransfer path provided on a downstream side of said positioning memberto transfer said light-sensitive material which has been transferredpassing over said positioning member further downstream, wherein theprojecting part of said positioning member is located on a side closerto said exposure device than the point of intersection of an extensionof said first transfer path and said optical axis and the point ofintersection of an extension of said second transfer path and saidoptical axis, and said positioning member has on its upstream side aninclined portion for guiding a forward end of said light-sensitivematerial transferred from said first transfer path onto said projectingpart.

According to this construction, the projecting part of the positioningmember is located on the side closer to the exposure device than thepoint of intersection of the extension of the first transfer path andthe optical axis and, therefore, a forward portion of thelight-sensitive material having been transferred by the first transferpath is brought into contact with the inclined portion on the upstreamside of the positioning member, guided onto the projecting part andexposed by the exposure device.

Further, a rear portion of the light-sensitive material is situated onthe side closer to the exposure device than the point of intersection ofthe extension of the second transfer path and the optical axis when thelight-sensitive material having been transferred by the first transferpath is passed to the second transfer path and transferred furtherdownstream. Thus, the rear portion of the light-sensitive material isprevented from lifting toward the exposure device and held in contactwith the projecting part so that the rear portion is exposed by theexposure device as it passes over the projecting part.

Consequently, proper exposures are made at both the forward and rearportions of the light-sensitive material even when it is curled.

Also, an image exposure apparatus according to the invention comprisesan exposure device for making line-by-line exposures of alight-sensitive material on an optical axis, a positioning memberprovided at a position facing said exposure device, a first transferpath provided on an upstream side of said positioning member to transfersaid light-sensitive material toward said positioning member, a secondtransfer path provided on a downstream side of said positioning memberto transfer said light-sensitive material having passed over saidpositioning member further downstream, and uplift-restraining means forpreventing said light-sensitive material from lifting from saidpositioning member toward said exposure device.

According to this construction, the light-sensitive material transferredby the first transfer path and the second transfer path is kept fromlifting from the positioning member toward the exposure device by theuplift-restraining means. As a consequence, the whole of thelight-sensitive material including its forward and rear portions isbrought into contact with the positioning member, and proper exposuresare made over the entire light-sensitive material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing the general construction of an imageprinting system according to a first embodiment of the invention;

FIGS. 2A, 2B, and 2C are diagrammatic representations of conditions inwhich a light-sensitive material is transferred over a projecting partof a positioning member in the image printing system shown in FIG. 1.

FIG. 2A is a diagram showing a condition in which a forward portion ofthe light-sensitive material is held in contact with the projecting partof the positioning member,

FIG. 2B is a diagram showing a condition in which a rear portion of thelight-sensitive material is held in contact with the projecting part ofthe positioning member, and

FIG. 2C is a diagram showing a condition in which a middle portion ofthe light-sensitive material excluding its forward portion and rearportion is held in contact with the projecting part of the positioningmember;

FIG. 3 is a diagram showing only a principal portion of an imageprinting system according to a second embodiment of the invention;

FIGS. 4A, 4B, and 4C are diagrammatic representations of conditions inwhich a light-sensitive material is transferred over a projecting partof a positioning member in the image printing system shown in FIG. 3,wherein

FIG. 4A is a diagram showing a condition in which a forward portion ofthe light-sensitive material is held in contact with the projecting partof the positioning member,

FIG. 4B is a diagram showing a condition in which a rear portion of thelight-sensitive material is held in contact with the projecting part ofthe positioning member, and

FIG. 4C is a diagram showing a condition in which a middle portion ofthe light-sensitive material excluding its forward portion and rearportion is held in contact with the projecting part of the positioningmember;

FIG. 5 is a diagram showing a variation of the image printing systemshown in FIG. 3;

FIG. 6 is a diagram showing another variation of the image printingsystem shown in FIG. 3;

FIG. 7 is a diagram showing only a principal portion of an imageprinting system according to a third embodiment of the invention;

FIG. 8 is a diagram showing a condition in which a light-sensitivematerial is transferred over a positioning member of the image printingsystem shown in FIG. 7;

FIG. 9 is a diagram showing a variation of the image printing systemshown in FIG. 7;

FIG. 10 is a diagram showing another variation of the image printingsystem shown in FIG. 7; and

FIG. 11 is a diagram showing a principal portion of a conventional imageprinting system.

BEST MODES FOR CARRYING OUT THE INVENTION

FIG. 1 is a diagram showing the general construction of an imageprinting system 10 according to a first embodiment of the invention.Referring to this Figure, the image printing system 10 comprisesexposure section 20 which exposes a light-sensitive material likephotographic printing paper with an image and a developing section 40which develops the light-sensitive material exposed with the image.

The exposure section 20 is for exposing the light-sensitive material Plike photographic printing paper with a digital image. It comprises animage transfer unit 22, a light-sensitive material feeder 24 which islocated upstream (right side as illustrated) of the image transfer unit22 and feeds the light-sensitive material P like the photographicprinting paper to the image transfer unit 22, a first transfer path 26for transferring the light-sensitive material P fed from the side of thelight-sensitive material feeder 24 toward the image transfer unit 22,and a second transfer path 28 for transferring the light-sensitivematerial P exposed in the image transfer unit 22 toward the developingsection 40.

The image transfer unit 22 includes an exposure head 221 formed of aPLZT device which serves as an exposure device for converting image datainto light signals and outputting them onto the light-sensitive materialP, a driving circuit 222 for driving the exposure head 221, an imagedata output unit 223 for outputting the image data to the drivingcircuit 222, and a positioning member 225 for regulating the position ofpassage of the light-sensitive material P. As previously stated, thePLZT device is a shutter array which is formed of a transparentferroelectric ceramic material obtained by adding lanthanum to leadzirconate titanate and utilizes an electro-optical effect of thematerial.

The image data output unit 223 performs prescribed image processingoperation on image data obtained by reading a film image, for instance,with an image pickup device like a charge-coupled device (CCD) or onimage data delivered from an external system like a personal computer,and outputs the processed image data line by line or as a succession ofa few lines.

The positioning member 225 is made into a shape having a projecting part226, a first inclined portion 227 formed on an upstream side (right sideas illustrated) of the projecting part 226 and a second inclined portion228 formed on a downstream side (left side as illustrated) of theprojecting part 226, the projecting part 226 being disposed such that itis located on an optical axis L of the exposure head 221 and, as will bedescribed later, the light-sensitive material P passes over theprojecting part 226 in contact therewith. The exposure head 221 performsan exposure operation on the light-sensitive material P passing over theprojecting part 226 by converting the image data into light signals andoutputting the light signals line by line or as a succession of a fewlines.

The light-sensitive material feeder 24 includes a cartridge rack 241 anda pull-out roller pair 242 for pulling out the elongate light-sensitivematerial P which is wound in a cartridge MG located on the cartridgerack 241 and advancing the light-sensitive material P into the firsttransfer path 26.

Constructed of an upper guide plate 261 and a lower guide plate 262which are arranged face to face with each other, the first transfer path26 is disposed in such a way that it slopes toward the positioningmember 225. More particularly, the first transfer path 26 is disposedsuch that it is inclined downward from right to left as illustrated, asthe exposure head 221 is installed with its head surface 224 directeddownward in this embodiment.

A portion of the lower guide plate 262 is removed at a downstreamterminal portion 26 a of the first transfer path 26, and a toughflexible sheet element 263 attached to the positioning member 225 isdisposed at the removed portion of the lower guide plate 262. Thisflexible sheet element 263 is arranged such that its portion directlyfacing the upper guide plate 261 is in contact with the upper guideplate 261. A protective element 261 a formed of velvet, for instance, isadhered to an inside surface of the upper guide plate 261 to protect thelight-sensitive surface of the light-sensitive material P.

An extreme part 27 of the downstream terminal portion 26 a is located onthe upstream side (right side as illustrated) of the projecting part 226of the positioning member 225 at a position in the proximity of theprojecting part 226 so that an outlet 27 a for the light-sensitivematerial P is located in the same plane as a plane H₁ containing theprojecting part 226 of the positioning member 225. With thisarrangement, the projecting part 226 of the positioning member 225 issituated closer to the exposure head 221 than the point of intersectionof a downstream extension of the first transfer path 26 and the opticalaxis L of the exposure head 221. To discriminate the extreme part 27 ofthe downstream terminal portion 26 a from the first transfer path 26 interminology, the extreme part 27 is referred to as an extended partformed at an end of the first transfer path 26.

The first transfer path 26 is provided with a first pair of transferrollers 264 for intermittently transferring the light-sensitive materialP in specific steps and a cutter unit 265 located upstream of the firsttransfer rollers 264. With this arrangement, the light-sensitivematerial P pulled out of the cartridge MG is cut into a specified lengthand transferred by the first transfer roller pair 264 toward theexposure head 221 on the downstream side.

Constructed of an upper guide plate 281 and a lower guide plate 282which are arranged face to face with each other, the second transferpath 28 is disposed in such a way that it slopes toward the positioningmember 225. More particularly, the second transfer path 28 is disposedsuch that it is inclined upward from right to left as illustrated, asthe exposure head 221 is installed with its head surface 224 directeddownward in this embodiment.

A portion of the lower guide plate 282 is removed at an upstreamterminal portion 28 a of the second transfer path 28, and a toughflexible sheet element 283 attached to the positioning member 225 isdisposed at the removed portion of the lower guide plate 282. Thisflexible sheet element 283 is arranged such that its portion directlyfacing the upper guide plate 281 is in contact with the upper guideplate 281. A protective element 281 a formed of velvet, for instance, isadhered to an inside surface of the upper guide plate 281 to protect thelight-sensitive surface of the light-sensitive material P.

An extreme part 29 of the upstream terminal portion 28 a of the upperguide plate 281 is partly bent toward the head surface 224 where theupper guide plate 281 is situated below the head surface 224 so that aninlet 29 a for the light-sensitive material P is located in the sameplane as the plane H₁ containing a top surface of the projecting part226 of the positioning member 225. With this arrangement, the projectingpart 226 of the positioning member 225 is situated closer to theexposure head 221 than the point of intersection of an upstreamextension of the second transfer path 28 and the optical axis L of theexposure head 221. To discriminate the extreme part 29 of the upstreamterminal portion 28 a from the second transfer path 28 in terminology,the extreme part 29 is referred to as an extended part formed at an endof the second transfer path 28.

The second transfer path 28 is provided with a second pair of transferrollers 284 for intermittently transferring the light-sensitive materialP in specific steps. The light-sensitive material P exposed by theexposure head 221 is transferred by the second transfer roller pair 284toward the developing section 40.

As the first transfer path 26 and the second transfer path 28 are formedas described above in the image printing system 10 of the foregoingconstruction, the light-sensitive material P passes over the projectingpart 226 of the positioning member 225 in conditions shown in FIGS. 2Ato 2C.

Firstly, since the light-sensitive material P is transferred downslopeleftward, a forward portion P₁ of the light-sensitive material P fedthrough the first transfer path 26 has a large angle of approach withrespect to the projecting part 226, and because the projecting part 226is situated closer to the exposure head 221 than the point ofintersection of the extension of the first transfer path 26 and theoptical axis L of the exposure head 221, the forward portion P₁ of thelight-sensitive material P goes into contact with the first inclinedportion 227 of the positioning member 225 and is guided along itsinclined surface toward the projecting part 226, as shown in FIG. 2A.Therefore, out-of-focus conditions will not occur at the forward portionP₁ of the light-sensitive material P as well, and a proper exposure willbe obtained. Furthermore, since the forward portion P₁ is kept fromlifting upward from the projecting part 226 (i.e., toward the exposurehead 221) by the extreme part 27, the forward portion P₁ is always heldin contact with the projecting part 226 as it passes over the projectingpart 226 no matter in which direction the light-sensitive material P iscurled (whether it is curled to form an upward- or downward-directedswelling). The extreme part 27 is not absolutely essential, however, forkeeping the forward portion P₁ of the light-sensitive material P incontact with the projecting part 226. This extreme part 27 may bedisposed such that its outlet 27 a is positioned below the plane H₁containing the projecting part 226 (i.e., on the side opposite to thehead surface 224 with respect to the plane H₁) as long as the extremepart 27 is situated within a range where it can guide thelight-sensitive material P which has been transferred through the firsttransfer path 26 onto the projecting part 226 along the inclined surfaceof the first inclined portion 227.

Even when the light-sensitive material P is significantly curled, itscurled portion is pressed and temporarily straightened since theflexible sheet element 263 of the downstream terminal portion 26 a ofthe first transfer path 26 is held in contact with the upper guide plate261 in this embodiment. Thus, the curled portion is brought into contactwith the projecting part 226 in a reliable fashion.

When the forward portion P₁ of the light-sensitive material P has passedfrom the first transfer path 26 into the second transfer path 28 and itsrear portion P₂ has been sent out from the first transfer path 26, thelight-sensitive material P is transferred upward to the left.Accordingly, the rear portion P₂ of the light-sensitive material P has alarge angle of departure with respect to the projecting part 226, andbecause the projecting part 226 is situated closer to the exposure head221 than the point of intersection of the extension of the secondtransfer path 28 and the optical axis L of the exposure head 221, therear portion P₂ is always held in contact with the projecting part 226as it passes over the projecting part 226, as shown in FIG. 2C.Therefore, out-of-focus conditions will not occur even at the rearportion P₂ of the light-sensitive material P, and a proper exposure willbe obtained. Furthermore, since the rear portion P₂ is kept from liftingupward from the projecting part 226 (i.e., toward the exposure head 221)by the extreme part 29, the rear portion P₂ is always held in contactwith the projecting part 226 as it passes over the projecting part 226no matter in which direction the light-sensitive material P is curled.The extreme part 29 is not absolutely essential, however, for keepingthe rear portion P₂ of the light-sensitive material P in contact withthe projecting part 226. This extreme part 29 may be disposed such thatits inlet 29 a is positioned below the plane H₁ containing theprojecting part 226 (i.e., on the side opposite to the head surface 224with respect to the plane H₁) as long as the extreme part 29 is situatedwithin a range where it can receive the light-sensitive material P whichhas been transferred through the first transfer path 26.

Even when the light-sensitive material P is significantly curled, itscurled portion is pressed and temporarily straightened since theflexible sheet element 283 of the upstream terminal portion 28 a of thesecond transfer path 28 is held in contact with the upper guide plate281 in this embodiment. Thus, the rear portion P₂ is brought intocontact with the projecting part 226 in a reliable fashion. Todiscriminate the extreme part 29 of the upstream terminal portion 28 afrom the second transfer path 28 in terminology, the extreme part 29 isreferred to as the extended part formed at the end of the secondtransfer path 28 in this embodiment.

When the light-sensitive material P is transferred as it spans betweenthe first transfer path 26 and the second transfer path 28, or when amiddle portion of the light-sensitive material P excluding its forwardportion P₁ and rear portion P₂ is transferred, the light-sensitivematerial P is kept from lifting upward from the projecting part 226 bythe extreme part 27 of the first transfer path 26 and the extreme part29 of the second transfer path 28 and held in contact with theprojecting part 226 as shown in FIG. 2B. Therefore, a proper exposure isobtained at the middle portion as well. This means that the extreme part27 (extended part) of the downstream terminal portion 26 a and theextreme part 29 (extended part) of the upstream terminal portion 28 aconstitute contact means for preventing the light-sensitive material Pfrom lifting upward toward the exposure head 221.

If the whole of the light-sensitive material P including its forwardportion P₁ and rear portion P₂ is properly exposed as described above,it becomes unnecessary to cut and throw away neither the forward portionP₁ or rear portion P₂ of the light-sensitive material P so that lossesof the light-sensitive material P can be reduced. Furthermore, itbecomes possible to reduce processing time of the system because thetime required for the cutting operation becomes unnecessary. Moreover,it becomes possible to use a lens having a small depth of focus in theexposure head 221 and improve its capability of exposing thelight-sensitive material P.

The developing section 40 comprises a plurality of processing tanks 401filled with processing solutions for developing the light-sensitivematerial P which has been exposed with images in the image transfer unit22, transfer means 402 for transferring the light-sensitive material Pin the processing tanks 401, a drying chamber 403 for drying thelight-sensitive material P discharged from the processing tanks 401, anda light-sensitive material delivery section 404 for ejecting the driedlight-sensitive material P onto vertically arranged trays which are notillustrated.

The image printing system 10 constructed as described above iscontrolled by a controller formed of a central processing unit (CPU), aread-only memory (ROM) in which a specific program is stored, arandom-access memory (RAM) in which data is temporarily stored, and soon, and operates generally in the following manner.

Firstly, when a start switch is turned on, the light-sensitive materialP is continuously pulled out of the cartridge MG loaded on the cartridgerack 241 and transferred downstream through the first transfer path 26and successively cut into a specified size by the cutter unit 265. Cutpieces of the light-sensitive material P are successively transferred tothe image transfer unit 22, where each piece of the light-sensitivematerial P transferred over the projecting part 226 of the positioningmember 225 is exposed by the exposure head 221. More specifically, asthe light-sensitive material P is transferred intermittently in specificsteps, the image data is output from the exposure head 221 in the formof light signals line by line or as a succession of a few lines onto thelight-sensitive material P in synchronism with its movement to therebymake an exposure of the light-sensitive material P. This exposureoperation is performed properly on the whole of the light-sensitivematerial P including its forward portion P₁ and rear portion P₂ asstated above. Upon completion of the exposure operation, thelight-sensitive material P is transferred to the developing section 40through the second transfer path 28. The light-sensitive material P isthen developed and ejected to the light-sensitive material deliverysection 404.

Although the exposure of the light-sensitive material P is made as itpasses through the image transfer unit 22 downstream in theabove-described first embodiment, it may be modified so as to oncetransfer the light-sensitive material P to the downstream side bypassing it through the image transfer unit 22 and then expose thelight-sensitive material P while reversing it to the upstream side.

Furthermore, although some portions of the lower guide plates 262, 282are taken away at the 26 a of the first transfer path 26 and at theupstream terminal portion 28 a of the second transfer path 28 and theflexible sheet elements 263, 283 are disposed at these portions,respectively in the above-described first embodiment, these flexiblesheet elements 263, 283 are not absolutely essential. It is possible toadopt a construction made up of the upper guide plates 261, 281 and thelower guide plates 262, 282 only without using the flexible sheetelements 263, 283.

Furthermore, although the light-sensitive material P is cut by thecutter unit 265 disposed in the first transfer path 26 and the exposureoperation is performed on the cut pieces of the light-sensitive materialP in the above-described first embodiment, it may be modified such thatthe cutter unit 265 is disposed in the second transfer path 28 and thelight-sensitive material P is cut after it has gone through the exposureoperation.

FIG. 3 is a diagram showing only a principal portion of an imageprinting system 100 according to a second embodiment of the invention.Since differences of this embodiment as compared to the image printingsystem 10 of the first embodiment lie only in the construction of theimage transfer unit 22 and its surrounding elements and the constructionand operation are otherwise basically unchanged, the followingdiscussion deals only with the differences from the image printingsystem 10. In addition, the same constituent elements are designated bythe same reference numerals and a detailed description of suchconstituent elements is not provided.

Specifically, this image printing system 100 is made such that apositioning member 225′ constituting part of an image transfer unit 22′is formed into a symmetrical shape having a projecting part 226′, afirst inclined portion 227′ formed on the upstream side (right side asillustrated) of the projecting part 226′ and a second inclined portion228′ formed on the downstream side (left side as illustrated) of theprojecting part 226′, and the projecting part 226′ is situated at aposition on an optical axis L of an exposure head 221. Further, a firstroller 30 is rotatably mounted beneath a head surface 224 on theupstream side of the positioning member 225′ while a second roller 32 isrotatably mounted beneath the head surface 224 on the downstream side ofthe positioning member 225′, wherein the first and second rollers 30, 32are disposed such that bottom parts of their surfaces lie in the samesurface as a plane H₂ containing a top surface of the projecting part226′.

A first transfer path 26′ on the upstream side of the exposure head 221and a second transfer path 28′ on its downstream side are disposed suchthat they have greater angles of inclination than the first and secondtransfer path 26, 28 of the first embodiment. A downstream terminalportion 26′a of the first transfer path 26′ and an upstream terminalportion 28′a of the second transfer path 28′ are situated apart from thehead surface 224 of the exposure head 221. A first pair of transferrollers 264′ is provided at the side of the downstream terminal portion26′a of the first transfer path 26′ facing the exposure head 221 while asecond pair of transfer rollers 284′ is provided at the side of theupstream terminal portion 28′a of the second transfer path 28′ facingthe exposure head 221. The projecting part 226′ of the positioningmember 225′ is arranged such that it is situated closer to the exposurehead 221 than both the point of intersection of an extension of thefirst transfer path 26′ and the optical axis L of the exposure head 221and the point of intersection of an extension of the second transferpath 28′ and the optical axis L of the exposure head 221.

The image printing system 100 of the aforementioned construction is madesuch that the projecting part 226′ of the positioning member 225′, thebottom parts of the surfaces of the first and second rollers 30, 32 andthe first and second transfer roller pairs 264′, 284′ are located on acircumference of a small diameter (e.g., 40 mmφ) shown by a chain line,making it possible to properly expose a forward portion P₁ and a rearportion P₂ of a light-sensitive material P even when the light-sensitivematerial P is curled to form a swelling of a 40 mmφ diameter directeddownward as illustrated, for example.

More particularly, since the light-sensitive material P is transferredfrom the first transfer path 26′ at a large angle of approach withrespect to the positioning member 225′ and the projecting part 226′ ofthe positioning member 225′ is situated closer to the exposure head 221than the point of intersection of the extension of the first transferpath 26′ and the optical axis L of the exposure head 221 in thisconstruction, the forward portion P₁ of the light-sensitive material Pgoes into contact with the first inclined portion 227′ of thepositioning member 225′ and is guided along its inclined surface towardthe projecting part 226′, as shown in FIG. 4A. Therefore, out-of-focusconditions will not occur even at the forward portion P₁ of thelight-sensitive material P, and a proper exposure will be obtained.Furthermore, since the forward portion P₁ is kept from lifting upwardfrom the projecting part 226′ (i.e., toward the exposure head 221) bythe first roller 30, the forward portion P₁ is always held in contactwith the projecting part 226′ as it passes over the projecting part 226′no matter in which direction the light-sensitive material P is curled.The first roller 30 is not absolutely essential, however, for keepingthe forward portion P₁ of the light-sensitive material P in contact withthe projecting part 226.

When the first roller 30 is provided, it may be disposed such that thebottom part of its surface is positioned below the plane H₂ (i.e., onthe side opposite to the head surface 224 with respect to the plane H₂)as long as the first roller 30 is situated within a range where theforward portion P₁ of the light-sensitive material P transferred throughthe first transfer path 26′ goes into contact with the first roller 30at a position lower than its rotary shaft.

When the forward portion P₁ of the light-sensitive material P has passedfrom the first transfer path 26′ into the second transfer path 28′ andits rear portion P₂ has been sent out from the first transfer path 26′,the light-sensitive material P is transferred upward to the left.Accordingly, the rear portion P₂ of the light-sensitive material P has alarge angle of departure with respect to the projecting part 226′, andbecause the projecting part 226′ is situated closer to the exposure head221 than the point of intersection of the extension of the secondtransfer path 28′ and the optical axis L of the exposure head 221, therear portion P₂ is always held in contact with the projecting part 226′as it passes over the projecting part 226′, as shown in FIG. 4C.Therefore, out-of-focus conditions will not occur at the rear portion P₂of the light-sensitive material P as well, and a proper exposure will beobtained. Furthermore, since the rear portion P₂ is kept from liftingupward from the projecting part 226′ (i.e., toward the exposure head221) by the second roller 32, the rear portion P₂ is always held incontact with the projecting part 226′ as it passes over the projectingpart 226′ no matter in which direction the light-sensitive material P iscurled. The second roller 32 is not absolutely essential, however, forkeeping the rear portion P₂ of the light-sensitive material P in contactwith the projecting part 226′.

When the second roller 32 is provided, it may be disposed such that thebottom part of its surface is positioned below the plane H₂ (i.e., onthe side opposite to the head surface 224 with respect to the plane H₂)as long as the second roller 32 is situated within a range where theforward portion P₁ of the light-sensitive material P goes into contactwith the second roller 32 at a position lower than its rotary shaft.

When the light-sensitive material P is transferred as it spans betweenthe first transfer path 26′ and the second transfer path 28′, or when amiddle portion of the light-sensitive material P excluding its forwardportion P₁ and rear portion P₂ is transferred, the light-sensitivematerial P is kept from lifting upward from the projecting part 226′ bythe first roller 30 and the second roller 32 and held in contact withthe projecting part 226′ as shown in FIG. 4B. Therefore, a properexposure is obtained at the middle portion as well. This means that thefirst and second rollers 30, 32 constitute contact means for preventingthe light-sensitive material P from lifting upward toward the exposurehead 221.

Although the first transfer rollers 264′ are provided at the side of thedownstream terminal portion 26′a of the first transfer path 26′ facingthe exposure head 221 and the second transfer rollers 284′ are providedat the side of the upstream terminal portion 28′a of the second transferpath 28′ facing the exposure head 221 in the above-described secondembodiment, it may be modified such that the first transfer rollers 264′are provided at an upstream position of the first transfer path 26′while the second transfer rollers 284′ are provided at a downstreamposition of the second transfer path 28′, and the downstream terminalportion 26′a of the first transfer path 26′ is positioned close to thefirst roller 30 while the upstream terminal portion 28′a of the secondtransfer path 28′ is positioned close to the second roller 32.

Furthermore, although the first and second rollers 30, 32 are used asthe contact means in the above-described second embodiment, there may beprovided first jet means 34 like a jet nozzle on the upstream side ofthe projecting part 226′ and second jet means 36 like a jet nozzle onthe downstream side of the projecting part 226′ instead of the first andsecond rollers 30, 32, as shown in FIG. 5, wherein compressed gas, suchas air, is supplied from an unillustrated compressed gas source to thefirst and second jet means 34, 36. In this case, the light-sensitivematerial P is kept from lifting upward (i.e., toward the exposure head221) from the projecting part 226′ by the gas blown from the first andsecond jet means 34, 36.

Furthermore, suction means 37 like a suction nozzle may be providedinside the positioning member 225′ instead of the first and secondrollers 30, 32 in such a manner that a suction port 371 is located inthe projecting part 226′ as shown in FIG. 6. A negative pressure issupplied from a vacuum source 372 to the suction means 37. In this case,the light-sensitive material P is sucked by the negative pressuresupplied through the suction means 37 and kept from lifting upward(i.e., toward the exposure head 221) from the projecting part 226′. Thesuction port 371 of the suction means 37 may be separately provided onboth the upstream and downstream sides of the projecting part 226′.

FIG. 7 is a diagram showing only a principal portion of an imageprinting system 200 according to a third embodiment of the invention. Asis the case with the second embodiment, differences of this embodimentas compared to the image printing system 10 of the first embodiment lieonly in the construction of the image transfer unit 22 and itssurrounding elements and the construction and operation are otherwisebasically unchanged. Therefore, the following discussion deals only withthe differences from the image printing system 10. In addition, the sameconstituent elements are designated by the same reference numerals and adetailed description of such constituent elements is not provided.

Specifically, a positioning member 225″ constituting part of an imagetransfer unit 22″ is formed into a flat shape in this image printingsystem 200. There is provided an uplift-restraining member 38 made of alight-transmitting material in close contact with a head surface 224 ofan exposure head 221, wherein one side of the uplift-restraining member38 facing the positioning member 225″ has a curved shape. Theuplift-restraining member 38 serving as uplift-restraining means isdisposed such that a peak 381 of its curved surface directed toward thepositioning member 225″ lies on an optical axis L of the exposure head221.

A first transfer path 26″ on the upstream side of the exposure head 221and a second transfer path 28″ on its downstream side are disposed suchthat they have smaller angles of inclination than the first and secondtransfer path 26, 28 of the first embodiment. A downstream terminalportion 26″a of the first transfer path 26″ and an upstream terminalportion 28″a of the second transfer path 28″ are situated apart from thehead surface 224 of the exposure head 221. A first pair of transferrollers 264″ is provided at the side of the downstream terminal portion26″a of the first transfer path 26″ facing the exposure head 221 while asecond pair of transfer rollers 284″ is provided at the side of theupstream terminal portion 281′a of the second transfer path 28″ facingthe exposure head 221.

Since a forward portion of a light-sensitive material P fed through thefirst transfer path 26″ has a large angle of approach with respect tothe positioning member 225″ in the image printing system 200 of theaforementioned construction, the light-sensitive material P is fed intoa gap between the uplift-restraining member 38 and the positioningmember 2251′ in a reliable fashion. The light-sensitive material P fedin between the uplift-restraining member 38 and the positioning member225″ is kept from lifting upward from the positioning member 225″ (i.e.,toward the exposure head 221) by the peak 381 of the uplift-restrainingmember 38 and, therefore, the whole of the light-sensitive material Pincluding its forward portion P₁ and rear portion P₂ is properly exposedeven when the light-sensitive material P is curled in a certaindirection.

More particularly, since the light-sensitive material P is transferredfrom the first transfer path 26″ at a specified angle of approach withrespect to the positioning member 225″, the forward portion P₁ of thelight-sensitive material P is fed into the gap between theuplift-restraining member 38 and the positioning member 225″ and theforward portion P₁ is kept from lifting upward from the positioningmember 225″ by the peak 381 of the uplift-restraining member 38, asshown in FIG. 8. Consequently, the forward portion P₁ of thelight-sensitive material P is brought into contact with a surface areaof the positioning member 225″ located at a position facing the peak381, and a proper exposure is made at the forward portion P₁. Similarly,the rear portion P₂ of the light-sensitive material P and its middleportion excluding the forward portion P₁ and rear portion P₂ are alsobrought into contact with the surface area of the positioning member225″ located at the position facing the peak 381, and a proper exposureis made in either case. Since the uplift-restraining member 38 is formedof a light-transmitting material like glass, it does not cause anyproblem to the exposure of the light-sensitive material P.

Furthermore, since the forward portion P₁ of the light-sensitivematerial P which has gone over the positioning member 225″ has a largeangle of departure with respect to the positioning member 225″, thelight-sensitive material P is passed to the second transfer path 28″ ina reliable fashion.

Although the first transfer rollers 264″ are provided at the side of thedownstream terminal portion 26″a of the first transfer path 26″ facingthe exposure head 221 while the second transfer rollers 284″ areprovided at the side of the upstream terminal portion 28″a of the secondtransfer path 28″ facing the exposure head 221 in the above-describedthird embodiment, it may be modified such that the first transferrollers 264″ are provided at an upstream position of the first transferpath 26″ while the second transfer rollers 284″ are provided at adownstream position of the second transfer path 28″, and the downstreamterminal portion 26″a of the first transfer path 26″ is positioned closeto the uplift-restraining member 38 and the upstream terminal portion28″a of the second transfer path 28″ is positioned close to theuplift-restraining member 38.

Furthermore, although the uplift-restraining member 38 made of alight-transmitting material is used in the above-described thirdembodiment, there may be provided first and second jet means 34′, 36′formed of jet nozzles, for example, instead of the uplift-restrainingmember 38 on upstream and downstream sides of a point C of intersectionof the surface of the positioning member 225″ and the optical axis L insuch a way that outlets of the first and second jet means 34′, 36′ aredirected to the proximity of the point C of intersection, as shown inFIG. 9. Compressed gas, such as air, is supplied from an unillustratedcompressed gas source to the first and second jet means 34′, 36′, andthe light-sensitive material P is kept from lifting upward toward theexposure head 221 by the gas blown from the first and second jet means34′, 36′.

Furthermore, suction means 37′ like a suction nozzle may be providedinside the positioning member 225″ instead of the uplift-restrainingmember 38 in such a manner that a suction port 371′ is located in theproximity of the point C of intersection of the surface of thepositioning member 225″ and the optical axis L as shown in FIG. 10. Anegative pressure is supplied from a vacuum source 372′ to the suctionmeans 37′, and the light-sensitive material P is sucked by the negativepressure and kept from lifting upward toward the exposure head 221. Thesuction port 371′ of the suction means 37′ may be separately provided onboth the upstream and downstream sides of the point C of intersection.

Furthermore, although the first inclined portions 227, 227′ are formedas integral part of the positioning members 225, 225′ in theearlier-described first and second embodiments, it is possible toconstruct the first inclined portions 227, 227′ as separate elementsfrom the positioning members 225, 225′, respectively. The positioningmembers 225, 225′ are so called including the first inclined portions227, 227′ even when the first inclined portions 227, 227′ areconstructed as separate elements as described above.

Furthermore, although the first transfer paths 26, 26′, 26″ and thesecond transfer paths 28, 28′, 28″ are individually disposed at a slantto the exposure head 221 in the above-described first to thirdembodiments, it is possible to arrange the first transfer paths 26, 26′,26″ and the second transfer paths 28, 28′, 28″ in a straight line incases where the curl of the light-sensitive material P is not so large.

Furthermore, although a component formed of a PLZT device is used in theabove-described first to third embodiments, it is possible to employ anytype of component, such as a FOCRT (fiber-optic cathode ray tube), LED(light-emitting diode) array or fluorescent display tube, as long as itis capable of making line-by-line exposures.

As thus far described, an image exposure apparatus according to theinvention comprises an exposure device for exposing a light-sensitivematerial line-by-line on an optical axis, a positioning member providedat a position facing said exposure device and having a projecting partsituated on said optical axis on a side facing said exposure device, afirst transfer path provided on an upstream side of said positioningmember to transfer said light-sensitive material toward said positioningmember, and a second transfer path provided on a downstream side of saidpositioning member to transfer said light-sensitive material havingpassed over said positioning member further downstream, where theprojecting part of said positioning member is located on a side closerto said exposure device than the point of intersection of an extensionof said first transfer path and said optical axis and the point ofintersection of an extension of said second transfer path and saidoptical axis, and said positioning member has on its upstream side aninclined portion for guiding a forward end of said light-sensitivematerial transferred from said first transfer path onto said projectingpart.

With this arrangement, the projecting part of the positioning member islocated on the side closer to the exposure device than the point ofintersection of the extension of the first transfer path and the opticalaxis and, therefore, a forward portion of the light-sensitive materialwhich has been transferred by the first transfer path is brought intocontact with the inclined portion on the upstream side of thepositioning member, guided onto the projecting part and exposed by theexposure device.

Further, a rear portion of the light-sensitive material is situated onthe side closer to the exposure device than the point of intersection ofthe extension of the second transfer path and the optical axis when thelight-sensitive material which has been transferred by the firsttransfer path is passed to the second transfer path and transferredfurther downstream. Thus, the rear portion of the light-sensitivematerial is prevented from lifting toward the exposure device and heldin contact with the projecting part so that the rear portion is exposedby the exposure device as it passes over the projecting part. As aconsequence, it is possible to make proper exposures at both the forwardand rear portions of the light-sensitive material even when it iscurled.

The first and second transfer paths may be so disposed as toindividually incline toward the aforementioned positioning member.

With this arrangement, the forward portion of the light-sensitivematerial which has been transferred from the first transfer path isalways brought into contact with the inclined portion on the upstreamside of the positioning member, guided onto the projecting part andexposed by the exposure device as the forward portion passes over theprojecting part even when the light-sensitive material is significantlycurled, because the forward portion has a large angle of approach withrespect to the positioning member. Furthermore, when the light-sensitivematerial is transferred downstream by the second transfer path, the rearportion of the light-sensitive material is always held in contact withthe projecting part and exposed by the exposure device as it passes overthe projecting part, because the forward portion of the light-sensitivematerial has a large angle of departure with respect to the positioningmember. Consequently, it is possible to make proper exposures at boththe forward and rear portions of the light-sensitive material even whenit is significantly curled.

Furthermore, there may be provided contact means for causing thelight-sensitive material being transferred to come into contact with theaforementioned projecting part.

With this arrangement, the light-sensitive material being transferred bythe first transfer path and the second transfer path is prevented fromlifting toward the exposure device by the contact means and the entirelight-sensitive material is reliably held in contact with the projectingpart and, as a consequence, it is possible to make proper exposures alsoat a middle portion of the light-sensitive material other than itsforward portion and rear portion in the same way as the forward and rearportions. In other words, it becomes possible to make proper exposuresover the entire light-sensitive material.

Furthermore, the aforementioned contact means may be constructed of anextended part formed at an end of at least one of the first and secondtransfer paths.

With this arrangement, the light-sensitive material transferred by thefirst transfer path and the second transfer path is prevented fromlifting toward the exposure device by the extended part formed at theend(s) of the transfer path(s) and the entire light-sensitive materialis reliably held in contact with the projecting part, and as aconsequence, it is possible to make proper exposures over the entirelight-sensitive material including its forward and rear portions.

Furthermore, the aforementioned contact means may include roller(s).

With this arrangement, the light-sensitive material transferred by thefirst transfer path and the second transfer path is prevented fromlifting toward the exposure device by the rollers and the entirelight-sensitive material is reliably held in contact with the projectingpart, and as a consequence, it is possible to make proper exposures overthe entire light-sensitive material including its forward and rearportions.

Furthermore, the aforementioned contact means may include means forforcing the light-sensitive material toward the projecting part with theuse of a blow-out force or a sucking force.

With this arrangement, the light-sensitive material transferred by thefirst transfer path and the second transfer path is prevented fromlifting toward the exposure device by the means using the blow-out forceor sucking force and the entire light-sensitive material is reliablyheld in contact with the projecting part. As a consequence, it ispossible to make proper exposures over the entire light-sensitivematerial including its forward and rear portions.

Also, an image exposure apparatus according to the invention comprisesan exposure device for exposing a light-sensitive material line-by-lineon an optical axis, a positioning member provided at a position facingsaid exposure device, a first transfer path provided on an upstream sideof said positioning member to transfer said light-sensitive materialtoward said positioning member, a second transfer path provided on adownstream side of said positioning member to transfer saidlight-sensitive material having passed over said positioning memberfurther downstream, and uplift-restraining means for preventing saidlight-sensitive material from lifting from said positioning membertoward said exposure device.

With this arrangement, the light-sensitive material transferred by thefirst transfer path and the second transfer path is kept from liftingfrom the positioning member toward the exposure device by theuplift-restraining means. As a result, the whole of the light-sensitivematerial is brought into contact with the positioning member, and properexposures can be made over the entire light-sensitive material includingits forward and rear portions with a simple construction.

The first and second transfer paths may be so disposed as toindividually incline toward the aforementioned positioning member.

With this arrangement, the forward portion of the light-sensitivematerial which has been transferred from the first transfer path isreliably fed into a gap between the positioning member and theuplift-restraining means and exposed on the positioning member by theexposure device even when the light-sensitive material is significantlycurled, because the forward portion has a large angle of approach withrespect to the positioning member.

Furthermore, the rear portion of the light-sensitive material which haspassed the positioning member is reliably fed into the second transferpath because the forward portion has a large angle of approach withrespect to the positioning member. Consequently, it is possible to makeproper exposures over the entire light-sensitive material including itsforward and rear portions even when it is curled.

The aforementioned uplift-restraining means may be formed of arestraining member which is made of a light-transmitting material anddisposed between the exposure device and the positioning member, whereinone side of the restraining member is directed to the positioning memberis formed into a curved shape having a peak (extremity of swelling part)lying on the optical axis.

With this arrangement, the light-sensitive material transferred by thefirst transfer path and the second transfer path is kept from liftingtoward the exposure device by the peak of the uplift-restraining meansformed of the light-transmitting material. As a result, the whole of thelight-sensitive material is brought into contact with the positioningmember, and proper exposures can be made over the entire light-sensitivematerial including its forward and rear portions with a simpleconstruction.

Furthermore, the aforementioned uplift-restraining means may includemeans for forcing the light-sensitive material toward the positioningmember with the use of a blow-out force or a sucking force.

With this arrangement, the light-sensitive material transferred by thefirst transfer path and the second transfer path is prevented fromlifting toward the exposure device by the means using the blow-out forceor sucking force and the entire light-sensitive material is reliablyheld in contact with the projecting part. As a consequence, it ispossible to make proper exposures over the entire light-sensitivematerial including its forward and rear portions with a simpleconstruction.

INDUSTRIAL APPLICABILITY

Since an image exposure apparatus of the invention is constructed suchthat a projecting part of a positioning member is located on a sidecloser to an exposure device than either the point of intersection of anextension of a first transfer path and an optical axis or the point ofintersection of an extension of a second transfer path and the opticalaxis and the positioning member has on its upstream side an inclinedportion for guiding a forward portion of the light-sensitive material,which has been transferred from the first transfer path, onto theprojecting part, it is possible to make proper exposures at both theforward and rear portions of the light-sensitive material even when itis curled.

Also, since an image exposure apparatus of the invention is providedwith a positioning member which is located at a position facing anexposure device as well as uplift-restraining means for preventing alight-sensitive material from lifting toward said exposure device, it ispossible to make proper exposures over the entire light-sensitivematerial including its forward and rear portions with a simpleconstruction.

What is claimed is:
 1. A light-sensitive material exposure apparatuscomprising: an exposure device for exposing a light-sensitive materialline by line on an optical axis; a positioning member provided at aposition facing said exposure device and having a projecting partsituated on said optical axis on a side facing said exposure device; afirst transfer path provided on an upstream side of said positioningmember to transfer the light-sensitive material toward said positioningmember; and a second transfer path provided on a downstream side of saidpositioning member to transfer the light-sensitive material havingpassed over said positioning member further downstream; wherein theprojecting part of said positioning member is located on a side closerto said exposure device than an intersection between a line extendedfrom said first transfer path and said optical axis and an intersectionbetween a line extending from said second transfer path and said opticalaxis, and said positioning member has on its upstream side an inclinedportion for guiding a forward end of the light-sensitive materialtransferred from said first transfer path onto said projecting part. 2.A light-sensitive material exposure apparatus as recited in claim 1,wherein said first and second transfer paths are inclined toward saidpositioning member.
 3. A light-sensitive material exposure apparatus asrecited in claim 1, further comprising contact means for causing thelight-sensitive material being transferred to come into contact withsaid projecting part.
 4. A light-sensitive material exposure apparatusas recited in claim 3, wherein said contact means includes an extendedpart formed at an end of at least one of said first and second transferpaths.
 5. A light-sensitive material exposure apparatus as recited inclaim 4, wherein said extended part is bent in a direction toward saidexposure device.
 6. A light-sensitive material exposure apparatus asrecited in claim 3, wherein said contact means includes a roller.
 7. Alight-sensitive material exposure apparatus as recited in claim 3,wherein said contact means includes means for forcing thelight-sensitive material toward said projecting part using a blow-outforce or a suction force.
 8. A light-sensitive material exposureapparatus as recited in claim 3, wherein said contact means comprise atleast one jet nozzle through which fluid is directed toward saidprojecting part to prevent lifting of the light-sensitive materialupward from said projecting part.
 9. A light-sensitive material exposureapparatus as recited in claim 3, wherein said contact means comprise asuction port arranged in said projecting part and communicating with asource of negative pressure.
 10. A light-sensitive material exposureapparatus as recited in claim 1, wherein said first transfer pathcomprises a lower guide plate and an upper guide plate opposed to saidlower guide plate and extending beyond said lower guide plate at an endproximate said positioning member, further comprising a flexible sheetelement attached to said positioning member and in contact with saidupper guide plate, said flexible sheet element being arranged below saidupper guide plate at a location where said upper guide plate extendsbeyond said lower guide plate.
 11. A light-sensitive material exposureapparatus as recited in claim 1, wherein said first transfer pathcomprises a lower guide plate and an upper guide plate opposed to saidlower guide plate, further comprising a protective element attached toan inner surface of said upper guide plate to protect a light-sensitivesurface of the light-sensitive material during passage in said firsttransfer path.
 12. A light-sensitive material exposure apparatus asrecited in claim 1, wherein said second transfer path comprises a lowerguide plate and an upper guide plate opposed to said lower guide plateand extending beyond said lower guide plate at an end proximate saidpositioning member, further comprising a flexible sheet element attachedto said positioning member and in contact with said upper guide plate,said flexible sheet element being arranged below said upper guide plateat a location where said upper guide plate extends beyond said lowerguide plate.
 13. A light-sensitive material exposure apparatus asrecited in claim 1, wherein said second transfer path comprises a lowerguide plate and an upper guide plate opposed to said lower guide plate,further comprising a protective element attached to an inner surface ofsaid upper guide plate to protect a light-sensitive surface of thelight-sensitive material during passage in said second transfer path.14. A light-sensitive material exposure apparatus as recited in claim 1,wherein said positioning member has a symmetrical shape.
 15. Alight-sensitive material exposure apparatus as recited in claim 1,wherein said positioning member has on its downstream side an inclinedportion adjacent said projecting part.
 16. A light-sensitive materialexposure apparatus comprising: an exposure device for exposing alight-sensitive material line-by-line or as a succession of a few lines;a positioning member provided at a position facing said exposure deviceto support a portion of the light-sensitive material at its exposureposition; a first transfer path provided on an upstream side of saidpositioning member to transfer the light-sensitive material toward saidpositioning member; a second transfer path provided on a downstream aideof said positioning member to transfer the light-sensitive materialhaving passed over said positioning member further downstream; and arestraining member formed of a light-transmitting material and disposedbetween said exposure device and said positioning member, one side ofsaid restraining member facing said positioning member having a curvedconvex shape with a peak opposite to the exposure position.
 17. Alight-sensitive material exposure apparatus comprising: an exposuredevice for exposing a light-sensitive material line-by-line or as asuccession of a few lines: a positioning member provided at a positionfacing said exposure device to support a portion of the light-sensitivematerial at its exposure position; a first transfer path provided on anupstream side of, said positioning member to transfer thelight-sensitive material toward said positioning member; a secondtransfer path provided on a downstream side of said positioning memberto transfer the light-sensitive material having passed over saidpositioning member further downstream; and means for forcing thelight-sensitive material toward said positioning member with the use ofa blow-out or a suction force.
 18. A light-sensitive material exposureapparatus as recited in claim 17, wherein said means for forcing thelight-sensitive material toward said positioning member comprise atleast one jet nozzle through which fluid is directed toward saidprojecting member to prevent lifting of the light-sensitive materialupward from said projecting member.
 19. A light-sensitive materialexposure apparatus as recited in claim 17, wherein said means forforcing the light-sensitive material toward said positioning membercomprise a suction port arranged in said projecting member andcommunicating with a source of negative pressure.
 20. A light-sensitivematerial exposure apparatus, comprising: an exposure device for exposinga light-sensitive material line-by-line or as a succession of a fewlines; a positioning member provided at a position facing said exposuredevice to support a portion of the light-sensitive material at itsexposure position; a first transfer path provided on an upstream side of&aid positioning member to transfer the light-sensitive material towardsaid positioning member; a second transfer path provided on a downstreamside of said positioning member to transfer the height-sensitivematerial having passed over said positioning member further downstream;and a restraining device for urging the portion of the light-sensitivematerial under exposure against the positioning member; wherein saidfirst and second transfer paths incline towards said positioning memberand extend close to said positioning member to operate as saidretraining device.
 21. A light-sensitive material exposure apparatus,comprising: an exposure device for exposing a light-sensitive materialline-by-line or as a succession of a few lines; a positioning memberprovided at a position facing said exposure device to support a portionof the light-sensitive material at its exposure position; a firsttransfer path provided on an upstream side of said positioning member totransfer the light-sensitive material toward said positioning member; asecond transfer path provided on a downstream side of said positioningmember to transfer the light-sensitive material having passed over saidpositioning member farther downstream; and a restraining device forurging the portion of the light-sensitive material under exposureagainst the positioning member; wherein said positioning member includesa projection projecting toward said exposure device, and said first andsecond transfer paths incline toward said positioning member such thatimaginary extensions of the transfer paths intersect said projectorunder a top of said projection.
 22. A light-sensitive material exposureapparatus as recited in claim 21, wherein said positioning memberincludes guide surfaces on the upstream and downstream sides of saidprojection.
 23. A light-sensitive material exposure apparatus,comprising: an exposure device for exposing a light-sensitive materialline-by-line or as a succession of a few lines; a positioning memberprovided at a position facing said exposure device to support a portionof the light-sensitive material at its exposure position; a firsttransfer path provided on an upstream side of said positioning member totransfer the light-sensitive material toward said positioning member; asecond transfer path provided on a downstream side of said positioningmember to transfer the light-sensitive material having passed over saidpositioning member further downstream; and a restraining device forurging the portion of the light-sensitive material under exposureagainst the positioning member; wherein said restraining device includesa pair of urging members positioned close to the exposure position,respectively on the upstream side and downstream side of the exposureposition.
 24. An image printing apparatus, comprising: a light-sensitivematerial feeder for feeding a light-sensitive material an exposuredevice for exposing a light-sensitive material line-by-line or as asuccession of a few lines; a positioning member provided at a positionfacing said exposure device to support a portion of the light-sensitivematerial at its exposure position; a first transfer path provided on anupstream side of said positioning member to transfer toward saidpositioning member the light-sensitive material fed by saidlight-sensitive material feeder; a restraining device for urging aportion of the light-sensitive material under exposure against saidpositioning member; a second transfer path provided on a downstream sideof said positioning member to transfer, further downstream thelight-sensitive material having passed over said positioning member; anda developing section for developing the light-sensitive materialtransferred through the second transfer path; wherein said first andsecond transfer paths incline towards said positioning member and extendclose to said positioning member to operate as said retraining device.25. An image printing apparatus, comprising: a light-sensitive materialfeeder for feeding a light-sensitive material an exposure device forexposing a light-sensitive material line-by-line or as a succession of afew lines; a positioning member provided at a position facing saidexposure device to support a portion of the light-sensitive material atits exposure position; a first transfer path provided on an upstreamside of said positioning member to transfer toward said positioningmember the light-sensitive material fed by said light-sensitive materialfeeder; a restraining device for urging a portion of the light-sensitivematerial under exposure against said positioning member; a secondtransfer path provided on a downstream side of said positioning memberto transfer, further downstream, the light-sensitive material havingpassed over said positioning member; and a developing section fordeveloping the light-sensitive material transferred through the secondtransfer path; wherein said positioning member includes a projectionprojecting toward said exposure device, and said first and secondtransfer paths incline toward said positioning member such thatimaginary extensions of said first and second transfer paths intersectsaid projection under a top of said projection.
 26. An image printingapparatus, comprising: a light-sensitive material feeder for feeding alight-sensitive material an exposure device for exposing alight-sensitive material line-by-line or as a succession of a few lines;a positioning member provided at a position facing said exposure deviceto support a portion of the light-sensitive material at its exposureposition; a first transfer path provided on an upstream side of saidpositioning member to transfer toward said positioning member thelight-sensitive material fed by said light-sensitive material feeder; arestraining device for urging a portion of the light-sensitive materialunder exposure against said positioning member; a second transfer pathprovided on a downstream side of said positioning member to transfer,further downstream, the light-sensitive material having passed over saidpositioning member; and a developing section for developing thelight-sensitive material transferred through the second transfer path;wherein said restraining device including a pair of urging memberspositioned close to the exposure position, respectively on the upstreamside and downstream side of the exposure position.